1. Field of the Invention
The present invention relates to a liquid crystal display (LCD) apparatus, and more particularly to an apparatus for preventing light from being leaked in an LCD apparatus to improve quality of images displayed thereon.
2. Description of the Related Art
To display images, in general, an LCD apparatus precisely controls liquid crystal using its optical anisotropic properties. The liquid crystal may be controlled by means of an electric field. For this reason, the liquid crystal is interposed between two electrodes.
The liquid crystal is arranged in a predetermined direction determined by an alignment groove, and tilted in a predetermined angle with respect to the alignment groove, thereby precisely controlling light transmittance of the liquid crystal.
FIG. 1 is a cross-sectional view showing an LCD panel of a conventional LCD apparatus.
Referring to FIG. 1, in order to display images having a high resolution through the LCD panel, the LCD panel requires a structure that is proper to precisely control small areas of the liquid crystal 10. For this purpose, a common electrode 20 to which a reference voltage is applied is disposed on the liquid crystal 10. Pixel electrodes 30, 35 that are divided in accordance with the resolution are formed under the liquid crystal 10, and the pixel electrodes 30 and 35 are opposite to the common electrode 20. The pixel electrodes 30 and 35 are formed not to be electrically short-circuited each other. A power supply module 40 is commonly connected with the pixel electrodes 30 and 35 to supply a desired power voltage to the pixel electrodes 30 and 35.
When dividing the pixel electrodes 30 and 35 into more than two in order to display images having the high resolution, there is a very small gap W between the pixel electrodes 30 and 35. It is not possible to control the liquid crystal 10 positioned at the gap W. That is, it is not possible to display images through the gap W disposed between the pixel electrodes 30 and 35, so that the quality of the image is lowered due to the light emitted through the gap W.
To prevent the quality of images from being lowered, the gap W positioned between the pixel electrodes 30 and 35 is screened by means of a light intercepting layer 50 having a band shape. The light intercepting layer 50 screens the power supply module 40, so that a user cannot recognize the power supply module 40.
However, if more than two pixel electrodes 30 and 35 are formed, light leaks through the gap W due to a horizontal electric field generated between the pixel electrodes 30 and 35. The horizontal electric field is formed between the edges of the pixel electrodes 30 and 35 in a concentric circle shape, and the horizontal electric field affects the vertical electric field by which the liquid crystal 10 is arranged ideally. Also, the liquid crystal 10 has a property to be arranged in parallel to directions of the horizontal and vertical electric fields.
When the liquid crystal 10 is disposed in parallel to the horizontal electric field, a reverse tilted region 70 is formed. As shown in FIG. 1, the liquid crystal 10 is reversely tilted at the pixel electrode 30, which is disposed to face a rubbing direction of the alignment groove 65 formed on the alignment layer 60. The liquid crystal 10 in the reverse tilted region 70 cannot be controlled, so that the light is leaked through the reverse tilted region 70. The reverse tilted region 70 is called as a declination line, which causes a low-quality image display.